text: Jean-Yves Le Drian, who is visiting Mali, said a force of 1,000 would be left in place.
  France intervened militarily in January to oust Islamist militants who had taken over the north of the country.
  A UN force in Mali, Minusma, was due to number 12,000 by now - but is still less than half of that.
  At the height of the crisis, France had a force of about 4,500 in its former colony.
  In July, France handed over responsibility for security to Minusma - which has incorporated West African troops who backed the French offensive.
  But France's timetable to withdraw most of its forces by the end of the year has slipped.
  The 1,000 French soldiers left in Mali are intended to help fight the al-Qaeda-linked groups still targeting the vast desert northern region.
  "We will remain by the side of the Malian army, and also Minusma, for as long as it takes," AFP news agency quotes Mr Le Drian as saying.
  On Monday, UN peacekeepers found a large cache of explosives while on patrol near the northern town of Kidal.
  UN spokesman Olivier Salgado said the quantity of ammonium nitrate found could be used to make between 20 to 25 car bombs, the Associated Press news agency reports.
target: France is to reduce the number of its troops in Mali over the next three months by 60%, the French defence minister has said.